Printed circuit boards and other supporting members for electronic components are often connected to wires by electrical connectors having contacts for engaging standard-sized conducting members for the electronic components. In some applications, it is desirable to maintain the contacts at the same temperature, to avoid voltage and/or current distortion of thermal sensing conductors through contacts owing to temperature differences, and some commercially available switches have thus been provided with heat-conducting, electrically-insulating members that touch a plurality of contacts.